Centering shutter for photographic cameras



June 5, 1962 H. JUNGHANS ETAL 3,037,438

CENTERING SHUTTER FOR PHOTOGRAPH'IC CAMERAS Original Filed March 29,1952 United States Patent Ofitice 3,037,438 Patented June 5, 19623,037,438 CENTERING SHUTTER FOR PHOTOGRAPHIC CAMERAS Helmut Junghans,Eckenliof, Schramherg-Sulgen, Wurttemberg, Germany; Kurt von Zeppelin,Goethestrasse 30, and Rudolf Weber, Untere Schillerstrasse 24, both ofSchramberg, Wurttemberg, Germany Original application Mar. 29, 1952,Ser. No. 279,396, now Patent No. 2,891,456, dated June 23, 1959. Dividedand this application July 24, 1958, Ser. No. 750,808 14 Claims. (Cl.95-115) This invention relates to photographic devices and in particularto control of mechanisms associated with the shutters of cameras.

This application is a divisional application based on our co-pendingapplication, Serial Number 279,396, filed March 29, 1952, the co-pendingapplication now being Patent Number 2,891,456 which issued on June 23,1959.

It is an object of the invention to provide an improved shutter controlmechanism. More particularly it is an object of the invention to provideimprovements with respect to the structure disclosed and claimed in theaforesaid patent.

It is a further object of the invention to incorporate into a shuttercontrol mechanism a synchronizing device which enables shutteroperations and associated functions to be effected with an optimumaccuracy.

Still another object of the invention relates to the provision ofimproved means for initiating the operation of a flash bulb ignitionsystem.

More specifically, the objects of the invention include the provision ofa flash bulb ignition control cooperatively associated with a shuttercontrol mechanism in such a manner as to permit the selective control ofthe relative time at which a flash bulb is made to ignite.

Briefly, to achieve the objectives of the invention and in accordancewith one embodiment thereof, it is contemplated, for example, that ashutter drive device be provided with which is operatively associated asynchronization device, there being further provided a source of powersuch as one or more springs which are coupled to the shutter drive andsynchronization devices to provide power for operating the same. Arelease is provided which engages the synchronization device as well asthe shutter drive device to prevent operation of the same. This releaseis disengageable to permit actuation of the synchronization device andthe release itself is responsive to the actuated synchronization deviceto enable operation of the shutter drive device.

A flash bulb ignition system is provided, for example, which isselectively associated with one of a number of controls which are inturn associated with either the shutter drive device or thesynchronization device. Thus, by proper selection, a flash bulb ignitionsystem can be controlled by the synchronization device which is actuatedprior to the actuation of the shutter drive device whereby the flashbulb ignition system is actuated at a relative time which is early inthe sequence of shutter control operations; alternatively, the flashbulb ignition system can be controlled by means of a control on theshutter drive device so that the ignition of a flash bulb is effectivesubsequent to the time at which it would be effected if thesynchronization device were to be the con trolling mechanism.

It is to be noted in accordance with preferred embodiments of theinvention, that a release mechanism is provided for the shutter drivedevice which must necessarily act through the intermediary of thesynchronization device.

In other words, the release mechanism cannot, with the preferredembodiment of the invention, operate directly and independently tocomplete the actuation of the associated shutter.

Moreover, as a feature of the invention, there is provided a device fortensioning springs which provide power for the shutter drive andsynchronization devices which tensioning device assumes a cockedposition when power is available for the shutter drive andsynchronization devices and does not leave this position until theshutter drive device has been actuated. Consequently, the tensioningdevice serves as an indicator of readiness for operation as well asconstituting a means for providing a source of power.

In accordance with another feature of the invention, there isincorporated into the system an escapement mechanism which controls theoperation of the synchronization device after the same has beenactuated. The escapement mechanism serves to render the operation of thesynchronization device perfectly uniform so that, with mechanismsprovided by the invention, the period can always be judged with extremeaccuracy and the repeating of particular operations is always possible.

Still another feature of the invention relates to the particular detailsof a selector mechanism which enables the selection of flash bulbignition operations which, for the purpose of this application, will becharacterized, for example, as instantaneous and pre-ignition flash bulboperations.

Advantageously, the invention provides its benefits in a small, compactunit, the controls for which are readily available and easily engagedfor purposes of shutter contro Other objects, features and advantages ofthe invention will be apparent from the following detailed descriptionof a preferred embodiment as illustrated in the accompanying drawing inwhich:

FIGURE 1 is a plan view, partially in section, of a shutter controlmechanism embodying a synchronization device and flash bulb ignitionsystem in accordance with the provisions of the invention;

FIGURE 2 is a sectional side view of the structure of FEGURE 1, takenalong line 22 in FIGURE 1;

FIGURE 3 illustrates a portion of FIGURE 1 with the synchronizationdevice in readiness to be actuated;

FIGURE 4 illustrates the synchronization device in release position withthe shutter drive device locked against operation;

I FIGURE 5 illustrates the actuation of the flash bulb ignition systemby one of the controls noted above; and

FIGURE 6 is a side view of FIGURE 5.

For the details of a shutter mechanism itself, reference is made to theabove-noted patent inasmuch as the shutter mechanism itself is not shownin the drawing for purposes of clarity. Moreover, the particular sourceof power used to drive the shutter drive device can also be found in theaforementioned patent and is likewise not shown in the drawing in orderto provide for a clearer understanding of the details of the structurewhich is to be explained below.

In FIGURES 1-6, and with particular reference to FIGURE 1, the structureof the invention includes a housing 401, which supports all of thecontrols and devices which have been noted above. The housing 401defines a central opening 40111, through which a photographic image istransmitted and in which aperture a shutter mechanism (not shown)operates to close and open the same.

The structure further includes a tensioning lever 40 2, pivotallyjournalled on a pin 403, which is mounted on the housing 491. Pins 404and 405 are supported on the lever 40?. for the pivotal connection ofrods or levers (not shown) which operate through springs (not shown)which are placed under tension by movement of lever 402 and which intensioned condition serve as sources of power for actuating the shutterdrive device 406, the func- 3 tion of which is completely explained inthe aforementioned co-pending application.

Also rotatably mounted on the pin 403 is freely rotatable gear 407having a toothed periphery and including a projection 4070. The lever402 comprises a forked structure, the inside opening 402a having adimension which exceeds that of projection 407a on gear 407. The forkedstructure therefore loosely accommodates the projection 407a or, inother words, there is a certain amount of play existing between theseelements. This constitutes a feature of the invention whereby, althoughthe gear 407 can be rotated by means of the lever 402 so that these elements are displaceable to the tensioning position illus trated by thedash-dot lines, any force acting on the gear 407 and tending to rotatethe same through a small angle will not be transmitted to the lever 402,which as a consequence thereof retains a stationary tensioning position.Moreover, forces acting on the lever 40-2, through the intermediary ofpins 404 and 405, are not transmitted to the gear 407 which, as aconsequence, is virtually independent of said forces.

The teeth of gear 407 are engaged with teeth 408a on the synchronizationdevice or ring 408, which is coaxially and peripherally arrangedrelative to the circular aperture 401a. Actuating power for thesynchronization device 408 is provided by a spring 409, which may be anyconventional form of spring such as a helix. One end of the spring 409is engaged with the synchronization device 408 by means of a lug 410integral with the synchronization device 408. The other end of spring409 is secured to a bridge 411 fixed on the housing 401.

From the structure described above, it follows that the synchronizationdevice 408 has to be rotated in counterclockwise direction relative tothe position shown in FIG- URE 1 in order for this member to be placedunder tension and in readiness for operation. In other words, thecounter-clockwise rotation of synchronization device 408 places thespring 409 under tension and unless the synchronization device isrestricted against rotation, when spring 409 is under tension, thesynchronization device 408 will tend to return to its original positionas shown in FIGURE 1. It is to be noted, of course, that a movement oflever 402 from the posit-ion shown by the use of solid lines in FIGURE 1to the position shown in dashdot lines operates to place spring 409under tension and thus cock the synchronization device 408 and renderthe same ready for operation.

Actually, the operation of synchronization device 408 consists of twosequential operations, to wit: the tensioning operation described aboveand a releasing operation next indicated in detail.

When the synchronization device 408 has been cocked, it is held incocked position by means of abutments as will be described. To releasethe synchronization device, there is provided a release lever 413pivotally mounted on a pin 412 supported on housing 401. The lever 413is cooperatively associated with a locking lever 415 which is rotatablysupported on a pin 414 affixed to the housing 401. The lever 413functions through the intermediary of locking lever 415 to control thesynchronization device 408 and, through the intermediary thereof, the operation of shutter drive device 406.

The lever 415 includes a lug 415a engageable with lugs 406a and 40Gb onshutter drive device 406. Since the shutter mechanism, as described inour co-pending application, reverses its direction of movement betweenexposures, the shutter driving member 406 effects driving movementsalternately in opposite rotational directions. For that reason, 406a and40612 are provided against which lever 415 abuts for each operation ofthe mechanism.

The lever 415 has a second lug 415b with which the lever cooperates withsynchronization device 408. In tensioned condition (see FIG. 3),shoulder 4081) on the synchronization device 408 abuts against lug 415k.This locks the synchronization device 408 in tensioned or cockedcondition for subsequent release and actuation.

As will be explained in greater detail hereinafter, the shutter drivedevice 406 cannot be actuated directly by operation of members 413 and415, and this is instead effected indirectly by means of thesynchronization device 408 which, for purposes of this function, isprovided with a lifting cam 4080 (FIG. 4) which engages lever 415 whenthe synchronization device 408 has performed a flash bulb ignitionfunction as will subsequently be described.

in order to retard the escape or actuation of the synchronization device408, this member is controlled during actuation by an escapementmechanism 416 pivotally journalled on a pin 417 mounted on the bridge411 and on the housing 401. The escapement mechanism 416 cooperates withteeth 408d on the synchronization device 408 in a manner conventionalper se so that the movement of the synchronization device 408, in arotational sense, is both retarded and uniform.

To facilitate an understanding of the operation of the structure, it isnow simply indicated that the synchronization device 408 operates priorto the release or actuation of the shutter drive device 406. In orderthat the operation of the device provided in accordance with theinvention can be described as a whole, the fiash bulb ignition systemprovided in accordance with the invention is next indicated.

It has been noted above that the invention provides for the selectivetime control of the flash bulb ignition system. For this selection, aspring or blade 419 is provided and is affixed in electrically insulatedmanner to the housing 401 by means of a screw or bolt 418. The spring419, for purposes of this selecting function, is intended to be movedtoward or away from the plane of the drawing as indicated in FIG. 1 and,to prevent a rotational movement of the spring, the same is providedwith a slot 419a which is engaged by a stud 420 mounted on andelectrically insulated from the housing 401.

The spring 419 does not lay flat against the housing 401, but iselevated therefrom to define a space with the housing 401 to accommodatea blade-like extension 42111 on a control 421 (see FIGS. 5 and 6) forpurposes of displacement of the blade or spring 419. The control 421,which it will be noted extends externally of the housing 401, can bedisposed between two positions; one of these positions is indicated inFIG. 1 and causes the blade 421a to be disengaged from spring 419, andthe other position is indicated in FIGS. 5 and 6 by means of which blade421a engages spring 419 and causes the same to be lifted away fromhousing 401. It will be noted in the description that follows that theposition of spring 419 is determinative of the relative time at whichflash bulb ignition occurs.

The spring 419 includes an extension 4191) connected by an angle to themain body of spring 419. Extension 41912 is thus positioned in a planespaced parallel to the main section of spring 419. This is best seen inFIG. 6. Extension 41% supports two contacts 419a and 419d on oppositesides of the said extension. Contact 4190 is effective for one type offlash bulb ignition operation whereas contact 419d is utilized foranother flash bulb ignition operation. These two contacts, however, havecommon connection with an associated flash bulb ignition circuit and thespring 419 can be analogized somewhat to a single pole, double throwswitch. There are, however, no fixed contacts for contacts 419s and d toengage as will become hereinafter apparent.

For instantaneous ignition of the flash bulb, use is made of contact419d, the engagement of which is controlled by shutter drive device 406.Spring 419 is made ready for this operation by placing the control 421in such a position that blade 421a is out of engagement with spring 419.The positions of the various elements relatively to housing 401 is,under these conditions, indicated in FIG. 2. For this type of operation,a movement of synchronization device 408, while controlling theoperation of shutter drive device 406, is not employed for flash bulbignition purposes.

To employ the synchronization device 408, for flash bulb ignitionpurposes, control 421 is placed in the position indicated in FIG. 5where blade 421 engages spring 419 and elevates the same with respect tohousing 401. The position of the various elements relative to housing401 is, for this condition, best seen in FIG. 6. In this position,contact 419 is outside the range of contact 422 mounted on shutter drivedevice 406, and contact 4190 is within the range of spring mountedcontact 423b mounted on spring 423 supported on housing 401 by screw424. Spring 423 is in the nature of a cantilever spring and in the formof a blade the plane of which is perpendicular to the face of housing401 as best shown in FIG. 3. At the end of spring 423 opposite to thatend coupled by screw 424 to housing 401, the cantilever spring supportscontact 4231) for displacement by the synchronization device 408 and forwiping across the contact 4190 to close the ignition circuit.

Spring 423 cooperates by means of its edge 423a (see FIG. 5) with a cam408a adjacent recess 408] and a lifting cam 408g, all of which areincluded or defined by synchronization device 408. This structure isarranged in such a manner that when the synchronization device 408 iscooked, cam 4080 bends back spring 423 (see FIG. 3 for the manner inwhich device 408 is rotated counter clockwise). Spring edge 423a, underthese circumstances, rests or is accommodated in recess 408f.

After actuation of synchronization device 408, cam 408g carries spring423 in a counter-clockwise direction relative to screw 424, (see FIG.5), thus bringing contact 423b into engagement or contact with contact4190 on extension 4191) of spring 419 (see FIGS. 5 and 6). A furthermovement of synchronizaiton device 408 interrupts contact between thesetwo latter mentioned contacts with the spring 423 dropping from the cam408g.

The spring 419 is, as previously mentioned, coupled by screw 418 tohousing 401. The spring is supplied with current by a lead 424 connectedwith a terminal 425 mounted on the housing 401 and electricallyinsulated therefrom. Projection 421a is, of course, of insulatingmaterial so as not to short-circuit spring 419, and con tacts 4231: and422 are coupled to the housing 401 which thus constitutes a ground forcompleting a flash bulb ignition circuit.

The device has two types of operation as next explaincd:

For an instantaneous ignition, the control 421 is moved into theposition shown in FIGS. 1 and 2. Lever 402 is moved into tensioningposition so that shutter drive device 406 and synchronization device 408are brought into cocked position (see FIG. 3). The spring 409 is thustensioned and shutter drive member rests with shoulder 406a against lug415a, the synchronization device 408 resting with shoulder 40% againstlug 415b. With release lever 413 brought into release position (see FIG.4), lug 4151) releases synchronization device 408. Lugs 415a and 4151)are so relatively positioned that only the synchronization device 408 isreleased at this time, Whereas shutter drive device 406 is maintained incocked position by lug 415a.

As a result of the release of synchronization device 408, the same isactuated by spring 409 and the potential energy of spring 409 isconverted into kinetic energy until spring 409 assumes its normalposition of rest.

The movement of synchronization device 408 is retarded and rendereduniform by escapement mechanism 416.

Cam 408g bends spring 423 from the position shown in FIG. 3 to theposition shown in FIG. 5. However, no contact between contacts 423b and4190 is effected inasmuch as spring 419, is in a position closest tohousing 6 401 as shown in FIGS. 1 and 2. Thus, an ignition of the flashbulb is not effected by movement of synchronization device 408.

When synchronization device 408 approaches the end of its rotation, itslifting cam 4080 moves lever 415 into a full release position wherebylug 415a releases shutter drive device 406 for rotation. During rotationof shutter drive device 406 which is in clockwise direction, contact 422mounted on shutter drive device 406 slides over contact 419d which hasbeen appropriately positioned and closes the ignition circuit to ignitean associated flash bulb.

In the operation described above, the releasing of the synchronizationdevice has subsequently efl ected a release of the shutter drive deviceand a contact on the shutter drive device has been employed to effectflash bulb ignition. In order to enable the use of a flash bulb havingan ignition time of, for example, twenty milliseconds, the control 421is moved into the position illustrated in FIGS. 5 and 6. Consequently,the blade 421a elevates spring 419 bringing contact 4190 to the level ofcontact 4231) when the latter is in raised position due to displacementof spring 423. The contact between contacts 4190 and 42312 is controlledby the synchronization device 408. Movement of synchronization 408causes a displacement of spring 423, as described above, with aresulting engagement between contacts 4231; and 4190 to close theignition circuit before the actuation of shutter drive device 406 sothat the flash bulb has a period within which to reach its maximum lightintensity before the associated shutter is actuated.

In the above description, it is seen that a special control mechanismhas been provided wherein a release mechanism operates through themedium of a synchronization device to effect release of a shutter drivedevice. The shutter drive device is not directly operated by the releasebut is instead controlled by the synchronization device which operateson the release after having been itself actuated by the release.

Further, there has been provided a flash bulb ignition device controlledby elements electrically associated with controls coupled to thesequentially operating synchronization and shutter drive devices.

A source of power has been indicated in the form of a spring foroperation of the synchronization device and a lever is employed forbringing the synchronization device to a cocked position, the leversimultaneously serving to indicate that the shutter control mechanism isin readiness for operation.

There has further been employed an escapement mechanism to control themovement of the synchronization device when actuated and, in general, itis to be noted that the shutter drive and synchronization devicescomprise concentric, rotatable rings, the release comprising lugs forsequentially disengaging the rings to permit an actuation thereof.

An ignition system is provided for flash bulbs in the structure of theinvention whereby a contemporaneous or premature ignition is enabledrelative to the operation of an associated shutter.

There will be obvious to those skilled in the art, many modificationsand variations of the structures set forth. These modifications andvariations will not, however, depart from the spirit of the inventiondefined in the following claims.

What is claimed is:

1. A shutter control mechanism comprising shutter drive means,synchronization means operatively associated with and controlling theshutter drive means, said shutter drive means and synchronization meanscomprising concentric rotatable rings, means coupled to the rings foroperating the same, a release for engaging said rings and preventingrotation thereof, said release being disengageable from the ring of thesynchronization means to permit rotation thereof, said release beingresponsive to the rotation of said ring of the synchronization means tobe disengaged from the ring of the shutter drive means to permitrotation thereof, flashbulb ignition means and means for actuating thesame, and control means selectively engageable with at least one of therings of the shutter drive means and the synchronization means andcoupled to the means for actuating the ignition means for selectiveactuation of the ignition means.

2. A mechanism as claimed in claim 1 wherein said means for operatingthe rings comprises a spring coupled to the ring of the synchronizationmeans and a lever engaging the ring of the synchronization means todisplace the same against the action of the spring.

3. A mechanism as claimed in claim 1 wherein the ring of thesynchronization means comprises teeth on the periphery thereof, saidmechanism further comprising an escapement mechanism engaging the teethon said ring for controlling the actuated ring of the synchronizationmeans.

4. A mechanism as claimed in claim 1 wherein the ring of thesynchronization means comprises teeth on the periphery thereof and saidmeans for operating the rings comprises a spring coupled to the ring ofthe synchronization means for opposing its rotation in one directionwhile storing energy to rotate the ring in the opposite direction, agear engaging the teeth on the ring, and a lever engaging the gear forrotating the latter ring in said one direction.

5. A mechanism as claimed in claim 1 wherein said release comprises lugsfor engaging the rings and preventing rotation thereof, a lever coupledto and supporting the lugs, and a pivot supporting the lever; the ringof the synchronization means including a cam which on rotation of thelatter said ring engages said lever; the pivoting of said leverinitially releasing the ring of the synchronization means whereupon theengagement of the cam with the lever further displaces the lever torelease the ring of the shutter drive means.

6. A shutter control mechanism comprising ignition means for igniting aflashbulb, spring-loaded first and second concentric rings one of whichis adapted for a shutter actuation operation and the other of which isadapted for controlling the actuation of said one ring, means forcontrolling the rotation of said other ring to initiate the subsequentaction of said one ring, ignition actuating controls independentlycoupled to each of said rings, and selector means for selectivelycoupling the controls to the flashbulb ignition means to control therelative time of ignition.

7. A mechanism as claimed in claim 6 wherein the selector meanscomprises a cantilever spring, contacts on said spring, and means fordisplacing the spring; said controls comprising contacts for theengagement of the first said contacts in accordance with thedisplacement of the spring.

8. A mechanism as claimed in claim 6 wherein at least one of saidcontrols comprises a cam on one of said rings and a blade-supportedcontact displaceable by this ring during rotation thereof; said ignitionactuating controls comprising a contact for engaging the blade-supportedcontact; said ignition means comprising an electrical circuit coupled tosaid contacts,

9. A shutter control comprising a housing for the shutter and defining acircular aperture for photographic purposes, first and second ringsconcentric with the aperture and rotatably supported on the housing,said first ring being spring loaded and adapted to operate the shutter,a toothed portion on the second ring, a spring connected between thehousing and the second ring to resist rotation of the latter, a gear onthe housing and engaging the toothed portion, a lever engaging the gearto rotate the second ring against the force of the spring, shoulders onthe first and second rings, a lever pivoted on the housing, lugs on thepivoted lever for engaging the shoulders and holding the rings in cockedcondition, said second ring being releasable before the first ring bythe lugs, a cam on the second ring for the engagement of the pivotedlever on rotation of the second ring, means on the housing fordisplacing the pivoted lever to release the second ring, said camfurther displacing the pivoted lever to release the first ring for theactuation of the shutter, a fiashbulb ignition circuit, engageablecontacts in the circuit for opening and closing the same, a blade on thehousing and insulated therefrom for supporting two of the contacts inspaced relation but with common connection in the circuit, a controlmember for displacing the blade and said two contacts between twopositions spaced axially relative to the rings, a further bladesupporting a further one of the contacts for displacement to one of thepositions, and a cam on one of said rings for the displacement of saidfurther blade on rotation of said second ring, one of said ringssupporting another of the contacts for movement to the other of saidpositions.

10. A control as claimed in claim 9, wherein said second ring includes afurther toothed portion, and comprising an escapement mechanism on thehousing engaging the further toothed portion.

11. A control as claimed in claim 9 wherein the first said leverincludes a fork-shaped structure, said gear including a projectionloosely engaged by said structure.

12. A control as claimed in claim 9 wherein said displacing meanscomprises a release lever pivoted on the housing and extendingexternally thereof, said release lever detachably engaging the pivotlever.

13. A control as claimed in claim 9 comprising an extension on thecontrol member extending externally of said housing.

14. A control as claimed in claim 9 comprising a spring engaging thepivoted lever to urge the same into a shoulder-engaging position.

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